For the You Show this week I wanted to provide some demos for folks who could not turn up for our Audacity demo sessions (which turned out to be everyone but two people, Gail and Joseph, you guys are the best).
I had one I did a few years ago for ds106 where I had used some Mac desktop software; the thing that bothered me was that I completely missed out that while recording into my headset mic, the audience never heard the audio I was playing back in Audacity.
So I actually spent an hour this week re-editing the video. I did not even have the source files, so I downloaded my own video from YouTube, and re-edited it in iMovie to reinsert the missing audio — it meant downloading some of the sound effect clips, and a bit of lining things up in iMovie, and even adding a few arrows as pointers.
But I did not really want to do more post editing for a screencast.
For the first demo this week, it was in person in the Open Learning Lab. What I did was run a screen recording on my laptop and at the same time recorded the audio on my iPad.
Again, this ended up with me doing post editing in iMovie to put them together.
So I wanted to get a setup with I could record it all. The secret weapon is QuickTime Player which has a build in ability to record screen activity (no fancy shmancy Camtasia arrows and editing, but basic record and save)
These are the things I needed to coordinate; I need to on top of the screen action, both my voice and anything I play back as an example in Audacity.
Because of my ds106 Radio machinations, I have a piece of free software to do the kind of mixing needed- Ladiocast (which oddly has disappeared from the Apple App Store).
The thing that makes it work as an OS X add-on called Soundflower. You have in your system sound control, and ability to select audio sources for your audio inputs (internal microphone, USB headset etc) and outputs (speakers or headphones). Soundflower creates two “virtual audio sources”, one is called Soundflower 2 and the other Soundflower 64, and these can be routed to other applications.
The first step is changing all of my system audio output go to Soundflower 64. This means any sound an application makes, From the beeping of the audio volume to iTunes to video in YouTube, can no longer be hard through my speakers. But this then becomes one input into Ladio Cast as well as my Microphone- so I can grab the two sound sources I need on the left:
The red buttons underneath mean they are both being sent to the output sources on the right; which on the top I set to Soundflower 2 and my built in output (headphones so I can monitor the mix).
To recap, the sound coming out of Audacity when I click play gets routed to SoundFlower 64, and mixed in Ladiocast with the audio from my microphone.
When I am ready to start, in Quicktime movie player I select
New Screen Recording from the
File menu. The tricky part is knowing that the little drop down menu on the right lets me pick the audio source for the recording; I want to use Soundflower 2 which is the mix coming out of Ladiocast:
And that is what it takes to record a screen cast where I want to be able to mix my audio spoken into a mic with the sound any application on my computer makes.
Yes, I could go simpler, if I just did an open recording with the built in mic and let the sound play out of the speakers. But the recording quality is lesser and there’s a chance of getting some feedback from the speakers back into the mic.
Besides it’s just cool to use Ladiocast as a mixer; the added bonus is I can modulate the sound volumes at the incoming source level.
Top / Featured Image: cc licensed (BY-SA) flickr photo by me: http://flickr.com/photos/cogdog/15403780454